Cleaning apparatus for submerged surfaces

Abstract

A pool cleaner (1) has a suction head (2) with a flow interrupter having a ball (12) movable to interrupt a primary liquid flow through the suction head and a release means (16) is located downstream of the ball (12) and has a flow passage allowing an auxiliary liquid flow into the tube when the ball interrupts the primary liquid flow. The auxiliary flow abruptly dislodges the ball and allows primary liquid flow.

What I/We claim as new and desire to secure by Letters Patent is: 
     
       1. Cleaning apparatus arranged to clean a submerged surface, comprising a suction head with a liquid entrance which is locatable against the surface, and which is in communication with a tube projecting away from the entrance with its free end connectable to a suction hose, the suction head also having a flow interrupter with a closure member movable between an interruption position and a release position to periodically and abruptly interrupt a primary liquid flow in use from the suction entrance through the tube to the hose, thereby to cause the suction head to move along the surface in suction communication therewith, and clean the surface, characterised in that: a release means is located downstream of the closure member in the primary flow path of the tube, said release means has at least one liquid flow passage allowing an auxiliary liquid flow into the tube when the closure member in the interruption position interrupts the primary liquid flow, the flow passage being shaped to direct such auxiliary liquid flow in use to cause a force to operate on the closure member to thereby dislodge and move said closure member to the release position and allow the primary liquid flow.   
     
     
       2. Apparatus as claimed in claim 1 characterised in that the cross sectional flow area of the auxiliary flow passage and the primary liquid flow passage, together with the shaping of the auxiliary flow passage, are balanced to prevent excessive liquid flow through the auxiliary flow passage when the primary liquid flow occurs in use. 
     
     
       3. Apparatus as claimed in claim 2 characterised in that openings for the auxiliary flow have a flow control means which is movable from a rest position in response to increasing auxiliary flow pressure, to increase the cross sectional area of the auxiliary flow path into the auxiliary flow openings, and which is movable to return to the rest position with decrease in auxiliary flow pressure. 
     
     
       4. Apparatus as claimed in claim 1 characterised in that liquid flow openings are provided for the auxiliary flow into the tube, the openings being provided with a flow control means which is movable from a rest position in response to increasing auxiliary flow pressure, to increase the cross sectional area of the auxiliary flow openings, and which is movable to return to the rest position with decrease in auxiliary flow pressure. 
     
     
       5. Apparatus as claimed in claim 4 characterised in that the release means is located around the tube, and includes a throat wall around auxiliary flow openings in the tube, the wall defining an annular throat leading into the auxiliary flow openings in the tube. 
     
     
       6. Apparatus as claimed in claim 5 characterised in that the auxiliary flow openings in the tube are formed by four axially extending slots spaced equally around the circumference of the tube. 
     
     
       7. Apparatus as claimed in claim 6 characterised in that the flow control means is a resilient skirt extending in operative location radially inwardly from the throat wall, across the throat opening, and extending further axially around the tube towards the head. 
     
     
       8. Apparatus as claimed in claim 5 characterised in that the flow control means is a resilient skirt extending in operative location radially inwardly from the throat wall, across the throat opening, and extending further axially around the tube towards the head. 
     
     
       9. Apparatus as claimed in claim 8 characterised in that the axially directed portion forms a skirt which tapers from a widest position removed from the tube wall and spaced from the tube openings, to a narrower free end position in which the free end of the skirt is around the tube openings and adjacent the tube walls. 
     
     
       10. Apparatus as claimed in claim 4 characterised in that the throat wall has a concentric tubular stem threadedly engagable around a complementarily threaded end of the main flow tube from the cleaning head, which stem is securable by means of a threaded collar acting as a lock nut at the end of the stem. 
     
     
       11. Apparatus as claimed in claim 10 characterised in that a tube section passing through the release means and carrying the auxiliary flow openings, is threadedly securable within the tubular stem to be concentric with the main flow tube. 
     
     
       12. Apparatus as claimed in claim 11 characterised in that the said release means tube section carries a blind throat portion which is complementarily shaped to the throat portion leading to the tube openings, and which is spaced apart from the throat wall by spacer blocks. 
     
     
       13. Apparatus as claimed in claim 12 characterised in that the spacer blocks are spaced apart around the circumference of the abutting throat wall and blind throat portions, leaving openings in between spacer blocks which communicate with the throat. 
     
     
       14. Apparatus as claimed in claim 13 characterised in that the blocks are carried on a ring which is resilient and has radial formations clippable onto complementary radial formations around the outside of the throat wall and the blind throat portion. 
     
     
       15. Apparatus as claimed in claim 14 characterised in that the blocks are of resilient material, selected to provide a locking action under compression when the threaded parts are connected. 
     
     
       16. Apparatus as claimed in claim 1 characterised in that the auxiliary flow passage is dimensioned and shaped to allow the auxiliary flow in use to abruptly dislodge the closure member in use, and cause the closure member to move away from its interruption position and strike a rebound surface in the suction head. 
     
     
       17. Apparatus as claimed in claim 16 characterised in that the closure member is a ball which is movable to seat in the interruption position against a round throat in the suction entrance to thereby interrupt the primary liquid flow. 
     
     
       18. Apparatus as claimed in claim 17 characterised in that the rebound surface is located in the liquid flow path opposite the throat. 
     
     
       19. Apparatus as claimed in claim 18 characterised in that the rebound surface is shaped to direct the ball back to the throat surface after the ball has struck it. 
     
     
       20. Apparatus as claimed in claim 19 characterised in that the rebound surface has a convex shape. 
     
     
       21. Apparatus as claimed in claim 19 characterised in that the rebound surface has a flat shape. 
     
     
       22. Apparatus as claimed in claim 1 characterised in that the tube extends into the suction head to be axially rotatable in a sealed mounting where it enters the suction head. 
     
     
       23. Apparatus as claimed in claim 1 characterised in that an adjustable weight is locatable in selectable positions between the suction head and the free tube end and is spaced from the plane of operation of the suction head against the surface in use. 
     
     
       24. Apparatus as claimed in claim 23 characterised in that the adjustable weight is located on that side of the body which has generally the smallest angular distance from the operative plane of the suction head and hence the surface to be cleaned in use. 
     
     
       25. Apparatus as claimed in claim 24 characterised in that the adjustable weight is slidable along a path in at least one guide and includes securing means for securing it in association with the tube and suction head. 
     
     
       26. Apparatus as claimed in claim 25 characterised in that the securing means is a screw extending through the weight to be engagable with one of a plurality of flutes located along the path at spaced intervals.